《Kubernets部署篇：Centos7.6部署单机kubernetes1.17.4》

心已赠人 2023-01-15 03:41 279阅读 0赞

### 文章目录 ###

*  一、架构图
 *  二、部署环境
 *  三、环境初始化
 *   *  3.1、内核升级
     *  3.2、系统初始化配置
 *  四、Docker部署
 *  五、kubernetes部署
 *   *  5.1、设置kubernetes源
     *  5.2、安装kubelet、kubeadm和kubectl
     *  5.3、k8s相关镜像下载
     *  5.4、kubeadm初始化master节点
     *  5.5、配置kubectl
     *  5.6、配置flannel网络
     *  5.7、将master标记为可调度
     *  5.8、kubelet服务启动
 *  总结：整理不易，如果对你有帮助，可否点赞关注一下？

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# 一、架构图 #

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L20wXzM3ODE0MTEy_size_16_color_FFFFFF_t_70]

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# 二、部署环境 #

**操作系统：centos7.6.1810**  
**内核版本：5.4.13**  
**说明：建议操作系统选择centos7.5或centos7.6，centos7.2，centos7.3,centos7.4版本存在一定几率的kubelet无法启动问题。**

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# 三、环境初始化 #

## 3.1、内核升级 ##

**说明：centos7.6系统内核默认是3.10.0，这里建议内核版本为5.11.16。**

内核选择：
    kernel-lt（lt=long-term）长期有效
    kernel-ml（ml=mainline） 主流版本

**升级步骤如下：**

# 1、下载内核
    CSDN下载地址：https://download.csdn.net/download/m0_37814112/17047556
    wget https://elrepo.org/linux/kernel/el7/x86_64/RPMS/kernel-ml-5.11.16-1.el7.elrepo.x86_64.rpm
    
    # 2、安装内核
    yum localinstall kernel-ml-5.11.16-1.el7.elrepo.x86_64.rpm -y
    
    # 3、查看当前内核版本
    grub2-editenv list
    
    # 4、查看所有内核启动grub2
    awk -F \' '$1=="menuentry " {print i++ " : " $2}' /etc/grub2.cfg
    
    # 5、修改为最新的内核启动
    grub2-set-default 'CentOS Linux (5.11.16-1.el7.elrepo.x86_64) 7 (Core)'
    
    # 6、再次查看内核版本
    grub2-editenv list
    
    # 7、reboot重启服务器

--------------------

## 3.2、系统初始化配置 ##

# 1、修改主机名
    hostnamectl set-hostname k8s-master
    
    # 2、内核参数修改
    cat > /etc/sysctl.d/k8s.conf <<EOF vm.swappiness = 0 net.ipv4.ip_forward = 1 net.bridge.bridge-nf-call-iptables = 1 net.bridge.bridge-nf-call-ip6tables = 1 net.bridge.bridge-nf-call-arptables = 1 EOF
    sysctl --system 
    
    # 3、永久新增br_netfilter模块
    # k8s网络使用flannel，该网络需要设置内核参数bridge-nf-call-iptables=1，修改这个参数需要系统有br_netfilter模块。
    cat > /etc/rc.sysinit << EOF #!/bin/bash for file in /etc/sysconfig/modules/*.modules ; do [ -x $file ] && $file done EOF
    
    cat > /etc/sysconfig/modules/br_netfilter.modules << EOF modprobe br_netfilter EOF
    
    chmod 755 /etc/sysconfig/modules/br_netfilter.modules
    
    # 4、关闭防火墙
    systemctl stop firewalld && systemctl disable firewalld
    
    # 5、永久关闭selinux
    sed -i 's#SELINUX=enforcing#SELINUX=disabled#g' /etc/sysconfig/selinux
    sed -i 's#SELINUX=enforcing#SELINUX=disabled#g' /etc/selinux/config
    
    # 6、关闭swap
    swapoff -a && sed -i 's/.*swap.*/#&/' /etc/fstab
    
    # 7、安装ipvsadm
    yum install ipvsadm -y
    cat > /etc/sysconfig/modules/ipvs.modules <<EOF #!/bin/bash ipvs_modules="ip_vs ip_vs_lc ip_vs_wlc ip_vs_rr ip_vs_wrr ip_vs_lblc ip_vs_lblcr ip_vs_dh ip_vs_sh ip_vs_fo ip_vs_nq ip_vs_sed ip_vs_ftp nf_conntrack" for kernel_module in \${ipvs_modules}; do /sbin/modinfo -F filename \${kernel_module} > /dev/null 2>&1 if [ $? -eq 0 ]; then /sbin/modprobe \${kernel_module} fi done EOF
    chmod 755 /etc/sysconfig/modules/ipvs.modules && bash /etc/sysconfig/modules/ipvs.modules && lsmod | grep --color ip_vs >/dev/null
    lsmod | grep ip_vs
    
    # 8、修改文件描述符和进程数（根据实际情况修改）
    vim /etc/security/limits.conf
    root soft nofile 65535
    root hard nofile 65535
    root soft nproc 65535
    root hard nproc 65535
    root soft memlock unlimited
    root hard memlock unlimited
    * soft nofile 65535
    * hard nofile 65535
    * soft nproc 65535
    * hard nproc 65535
    * soft memlock unlimited
    * hard memlock unlimited
    
    # 9、reboot重启服务器（必须）

**如下图所示：**  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L20wXzM3ODE0MTEy_size_16_color_FFFFFF_t_70 1]

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# 四、Docker部署 #

# 1、安装依赖包
    yum install yum-utils device-mapper-persistent-data lvm2 -y 
    
    # 2、设置Docker源
    yum-config-manager --add-repo https://download.docker.com/linux/centos/docker-ce.repo
    或
    yum-config-manager --add-repo http://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo
    
    # 3、docker安装版本查看
    yum list docker-ce --showduplicates | sort -r
    
    # 4、指定安装的docker版本为18.09.9
    yum install docker-ce-18.09.9 docker-ce-cli-18.09.9 containerd.io -y
    
    # 5、启动Docker
    systemctl start docker && systemctl enable docker
    
    # 6、修改Cgroup Driver
    # 修改docker数据目录，默认是/var/lib/docker,建议数据目录为主机上最大磁盘空间目录或子目录
    vim /etc/docker/daemon.json
    { 
      "registry-mirrors": ["https://v16stybc.mirror.aliyuncs.com"],
      "exec-opts": ["native.cgroupdriver=systemd"],
      "graph": "/data/docker"  
    }
    systemctl daemon-reload && systemctl restart docker

**如下图所示：**  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L20wXzM3ODE0MTEy_size_16_color_FFFFFF_t_70 2]

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# 五、kubernetes部署 #

## 5.1、设置kubernetes源 ##

cat <<EOF > /etc/yum.repos.d/kubernetes.repo [kubernetes] name=Kubernetes baseurl=https://mirrors.aliyun.com/kubernetes/yum/repos/kubernetes-el7-x86_64/ enabled=1 gpgcheck=1 repo_gpgcheck=1 gpgkey=https://mirrors.aliyun.com/kubernetes/yum/doc/yum-key.gpg https://mirrors.aliyun.com/kubernetes/yum/doc/rpm-package-key.gpg EOF
    
    yum clean all && yum -y makecache

--------------------

## 5.2、安装kubelet、kubeadm和kubectl ##

# 1、版本查看
    yum list kubelet --showduplicates | sort -r
    
    # 2、安装1.17.4版本
    yum install kubelet-1.17.4 kubeadm-1.17.4 kubectl-1.17.4 -y

--------------------

## 5.3、k8s相关镜像下载 ##

vim get_image.sh 
    #!/bin/bash
    url=registry.cn-hangzhou.aliyuncs.com/google_containers
    version=v1.17.4
    images=(`kubeadm config images list --kubernetes-version=$version|awk -F '/' '{print $2}'`)
    for imagename in ${images[@]} ; do
      docker pull $url/$imagename
      docker tag $url/$imagename k8s.gcr.io/$imagename
      docker rmi -f $url/$imagename
    done
    # flannel网络镜像下载
    docker pull quay.io/coreos/flannel:v0.14.0-rc1

**如下图所示：**  
![在这里插入图片描述][20210425180133498.png]

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## 5.4、kubeadm初始化master节点 ##

# 1、创建初始化配置文件
    kubeadm config print init-defaults > kubeadm-config.yaml
    
    # 根据实际部署环境修改信息：
    vim kubeadm-config.yaml
    
    apiVersion: kubeadm.k8s.io/v1beta1
    kind: ClusterConfiguration
    networking:
      serviceSubnet: "10.96.0.0/16"  #service网段地址
      podSubnet: "10.48.0.0/16"      #pod网段地址
    kubernetesVersion: "v1.17.4"     #kubernetes版本
    controlPlaneEndpoint: "192.168.1.216:6443"  #apiserver地址
    apiServer:
      extraArgs:
        authorization-mode: "Node,RBAC"
        service-node-port-range: 30000-36000  #service端口范围
    imageRepository: ""
    ---
    apiVersion: kubeproxy.config.k8s.io/v1alpha1
    kind: KubeProxyConfiguration
    mode: "ipvs"
    
    # 3、初始化master
    kubeadm init --config=kubeadm-config.yaml --upload-certs --ignore-preflight-errors=all

**如下图所示：**  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L20wXzM3ODE0MTEy_size_16_color_FFFFFF_t_70 3]

--------------------

## 5.5、配置kubectl ##

mkdir -p $HOME/.kube
    sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
    sudo chown $(id -u):$(id -g) $HOME/.kube/config

--------------------

## 5.6、配置flannel网络 ##

# 1、下载官方模板文件
    wget https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml
    
    # 2、部署flannel网络
    kubectl create -f kube-flannel.yml
    
    # 3、根据实际情况修改kube-flannel.yml
    vim kube-flannel.yml
    ---
    apiVersion: policy/v1beta1
    kind: PodSecurityPolicy
    metadata:
      name: psp.flannel.unprivileged
      annotations:
        seccomp.security.alpha.kubernetes.io/allowedProfileNames: docker/default
        seccomp.security.alpha.kubernetes.io/defaultProfileName: docker/default
        apparmor.security.beta.kubernetes.io/allowedProfileNames: runtime/default
        apparmor.security.beta.kubernetes.io/defaultProfileName: runtime/default
    spec:
      privileged: false
      volumes:
      - configMap
      - secret
      - emptyDir
      - hostPath
      allowedHostPaths:
      - pathPrefix: "/etc/cni/net.d"
      - pathPrefix: "/etc/kube-flannel"
      - pathPrefix: "/run/flannel"
      readOnlyRootFilesystem: false
      # Users and groups
      runAsUser:
        rule: RunAsAny
      supplementalGroups:
        rule: RunAsAny
      fsGroup:
        rule: RunAsAny
      # Privilege Escalation
      allowPrivilegeEscalation: false
      defaultAllowPrivilegeEscalation: false
      # Capabilities
      allowedCapabilities: ['NET_ADMIN', 'NET_RAW']
      defaultAddCapabilities: []
      requiredDropCapabilities: []
      # Host namespaces
      hostPID: false
      hostIPC: false
      hostNetwork: true
      hostPorts:
      - min: 0
        max: 65535
      # SELinux
      seLinux:
        # SELinux is unused in CaaSP
        rule: 'RunAsAny'
    ---
    kind: ClusterRole
    apiVersion: rbac.authorization.k8s.io/v1
    metadata:
      name: flannel
    rules:
    - apiGroups: ['extensions']
      resources: ['podsecuritypolicies']
      verbs: ['use']
      resourceNames: ['psp.flannel.unprivileged']
    - apiGroups:
      - ""
      resources:
      - pods
      verbs:
      - get
    - apiGroups:
      - ""
      resources:
      - nodes
      verbs:
      - list
      - watch
    - apiGroups:
      - ""
      resources:
      - nodes/status
      verbs:
      - patch
    ---
    kind: ClusterRoleBinding
    apiVersion: rbac.authorization.k8s.io/v1
    metadata:
      name: flannel
    roleRef:
      apiGroup: rbac.authorization.k8s.io
      kind: ClusterRole
      name: flannel
    subjects:
    - kind: ServiceAccount
      name: flannel
      namespace: kube-system
    ---
    apiVersion: v1
    kind: ServiceAccount
    metadata:
      name: flannel
      namespace: kube-system
    ---
    kind: ConfigMap
    apiVersion: v1
    metadata:
      name: kube-flannel-cfg
      namespace: kube-system
      labels:
        tier: node
        app: flannel
    data:
      cni-conf.json: |
        { 
          "name": "cbr0",
          "cniVersion": "0.3.1",
          "plugins": [
            { 
              "type": "flannel",
              "delegate": { 
                "hairpinMode": true,
                "isDefaultGateway": true
              }
            },
            { 
              "type": "portmap",
              "capabilities": { 
                "portMappings": true
              }
            }
          ]
        }
      net-conf.json: |
        { 
          "Network": "10.48.0.0/16",  #这里的网段地址需要与kubeadm-config.yaml配置文件定义的必须保持一致
          "Backend": { 
            "Type": "vxlan"
          }
        }
    ---
    apiVersion: apps/v1
    kind: DaemonSet
    metadata:
      name: kube-flannel-ds
      namespace: kube-system
      labels:
        tier: node
        app: flannel
    spec:
      selector:
        matchLabels:
          app: flannel
      template:
        metadata:
          labels:
            tier: node
            app: flannel
        spec:
          affinity:
            nodeAffinity:
              requiredDuringSchedulingIgnoredDuringExecution:
                nodeSelectorTerms:
                - matchExpressions:
                  - key: kubernetes.io/os
                    operator: In
                    values:
                    - linux
          hostNetwork: true
          priorityClassName: system-node-critical
          tolerations:
          - operator: Exists
            effect: NoSchedule
          serviceAccountName: flannel
          initContainers:
          - name: install-cni
            image: quay.io/coreos/flannel:v0.14.0-rc1
            command:
            - cp
            args:
            - -f
            - /etc/kube-flannel/cni-conf.json
            - /etc/cni/net.d/10-flannel.conflist
            volumeMounts:
            - name: cni
              mountPath: /etc/cni/net.d
            - name: flannel-cfg
              mountPath: /etc/kube-flannel/
          containers:
          - name: kube-flannel
            image: quay.io/coreos/flannel:v0.14.0-rc1
            command:
            - /opt/bin/flanneld
            args:
            - --ip-masq
            - --kube-subnet-mgr
            resources:
              requests:
                cpu: "100m"
                memory: "50Mi"
              limits:
                cpu: "100m"
                memory: "50Mi"
            securityContext:
              privileged: false
              capabilities:
                add: ["NET_ADMIN", "NET_RAW"]
            env:
            - name: POD_NAME
              valueFrom:
                fieldRef:
                  fieldPath: metadata.name
            - name: POD_NAMESPACE
              valueFrom:
                fieldRef:
                  fieldPath: metadata.namespace
            volumeMounts:
            - name: run
              mountPath: /run/flannel
            - name: flannel-cfg
              mountPath: /etc/kube-flannel/
          volumes:
          - name: run
            hostPath:
              path: /run/flannel
          - name: cni
            hostPath:
              path: /etc/cni/net.d
          - name: flannel-cfg
            configMap:
              name: kube-flannel-cfg

**说明：官方模板文件只需要修改"Network": "10.48.0.0/16"这一字段，且这里的网段地址需要与kubeadm-config.yaml配置文件定义的必须保持一致。**

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## 5.7、将master标记为可调度 ##

# 当创建单机版的k8s时，这个时候master节点是默认不允许调度pod 的，需要执行
    kubectl taint nodes --all node-role.kubernetes.io/master-

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## 5.8、kubelet服务启动 ##

systemctl restart kubelet && systemctl enable kubelet
    [root@node6 install-kubernetes]# kubectl get nodes
    NAME         STATUS   ROLES    AGE   VERSION
    k8s-master   Ready    master   17m   v1.17.4

**说明：kubernetes单机版，就部署完成了。**

**下一章：[《Kubernets部署篇：Centos7.6部署kubernetes1.17.4一主多从》][Kubernets_Centos7.6_kubernetes1.17.4]**

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# 总结：整理不易，如果对你有帮助，可否点赞关注一下？ #

更多详细内容请参考：[企业级K8s集群运维实战][K8s]

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L20wXzM3ODE0MTEy_size_16_color_FFFFFF_t_70]: /images/20221022/e275c9e5c02340379474b9b892d327c8.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L20wXzM3ODE0MTEy_size_16_color_FFFFFF_t_70 1]: /images/20221022/b7e45abcb5104a2abeedbaeed92e113b.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L20wXzM3ODE0MTEy_size_16_color_FFFFFF_t_70 2]: /images/20221022/7c0815bb27d9485aba4a40873213f5d2.png
[20210425180133498.png]: /images/20221022/54fcb6643d184ee1924fc6a9bfd47bc8.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L20wXzM3ODE0MTEy_size_16_color_FFFFFF_t_70 3]: /images/20221022/2b6d4c47fcd14f17a840416771252012.png
[Kubernets_Centos7.6_kubernetes1.17.4]: https://blog.csdn.net/m0_37814112/article/details/115950084
[K8s]: https://blog.csdn.net/m0_37814112/category_10856504.html?spm=1001.2014.3001.5482